title: Alternative pathways for MHC class I presentation: a new function for autophagy.
abstract: The classical view that endogenous antigens are processed by the proteasome and loaded on MHC class I molecules in the endoplasmic reticulum, while exogenous antigens taken up by endocytosis or phagocytosis are degraded and loaded on MHC class II in lysosome-derived organelles, has evolved along with the improvement of our understanding of the cell biology of antigen-presenting cells. In recent years, evidence for alternative presentation pathways has emerged. Exogenous antigens can be processed by the proteasome and loaded on MHC class I through a pathway called cross-presentation. Moreover, endogenous antigens can be targeted to lytic organelles for presentation on MHC class II through autophagy, a highly conserved cellular process of self-eating. Recent evidence indicates that the vacuolar degradation of endogenous antigens is also beneficial for presentation on MHC class I molecules. This review focuses on how various forms of autophagy participate to presentation of these antigens on MHC class I.
authors.affiliation: Département de pathologie et biologie cellulaire, Université de Montréal, Montreal, Canada.
authors.forename: Magali
authors.initials: M
authors.lastname: Chemali
authors.forename: Kerstin
authors.initials: K
authors.lastname: Radtke
authors.forename: Michel
authors.initials: M
authors.lastname: Desjardins
authors.forename: Luc
authors.initials: L
authors.lastname: English
mesh_terms: D000818:Animals; D017951:Antigen Presentation / Q000276:immunology*; D001343:Autophagy / Q000276:immunology*; D045142:Cross-Priming / Q000276:immunology; D015395:Histocompatibility Antigens Class I / Q000276:immunology*; D000949:Histocompatibility Antigens Class II / Q000276:immunology*; D008247:Lysosomes / Q000276:immunology; D051379:Mice; D010455:Peptides / Q000276:immunology; D010587:Phagocytosis / Q000276:immunology; D046988:Proteasome Endopeptidase Complex / Q000276:immunology; D014617:Vacuoles / Q000276:immunology; D014777:Virus Diseases / Q000276:immunology
chemical_list: D015395:Histocompatibility Antigens Class I; D000949:Histocompatibility Antigens Class II; D010455:Peptides; D046988:Proteasome Endopeptidase Complex